Vulnerability in exim4 (USN-4934-2)

Summary

vulnerability in exim4 (USN-4934-2). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to `4.82-3ubuntu2.4+esm3` or later.

AI summary snake-internal / snake-material-v2

A vulnerability tracked as **USN-4934-2** has been found in exim4. Risk of unauthorized operations or information disclosure. CVSS score: ?/10. What to do: upgrade exim4 to **4.82-3ubuntu2.4+esm3** or later. If unsure, ask your IT team or search "exim4 USN-4934-2" on the vendor's site.

USN-4934-2 (exim4) — Patched: `4.82-3ubuntu2.4+esm3` — apply immediately Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs. Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

**A vulnerability** (unclassified) exists in exim4.

📍 Affected scope

exim4 — .

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure

🔧 How to fix

Update to **4.82-3ubuntu2.4+esm3**.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run `grep -r 'exim4' .` against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response Actions (7 steps)

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'exim4' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で `exim4` を grep し、稼働しているサービス・バージョンを把握する。
6
Apply patch patch
```
Upgrade exim4 to 4.82-3ubuntu2.4+esm3
```
ステージング環境で 4.82-3ubuntu2.4+esm3 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 3 で見つけた異常検知の続報チェックを含めること。
7
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 3 と同じログクエリでアラート再発が無いか継続監視。

Affected packages

Ubuntu:Pro:14.04:LTS exim4

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.82-3ubuntu2.4+esm3"}]}]

Ubuntu:Pro:16.04:LTS exim4

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.86.2-2ubuntu2.6+esm1"}]}]

References

advisory https://ubuntu.com/security/notices/USN-4934-2
report https://ubuntu.com/security/CVE-2020-28007
report https://ubuntu.com/security/CVE-2020-28008
report https://ubuntu.com/security/CVE-2020-28009
report https://ubuntu.com/security/CVE-2020-28011
report https://ubuntu.com/security/CVE-2020-28012
report https://ubuntu.com/security/CVE-2020-28013
report https://ubuntu.com/security/CVE-2020-28014
report https://ubuntu.com/security/CVE-2020-28015
report https://ubuntu.com/security/CVE-2020-28016
report https://ubuntu.com/security/CVE-2020-28017
report https://ubuntu.com/security/CVE-2020-28020
report https://ubuntu.com/security/CVE-2020-28022
report https://ubuntu.com/security/CVE-2020-28024
report https://ubuntu.com/security/CVE-2020-28025
report https://ubuntu.com/security/CVE-2020-28026
report https://ubuntu.com/security/CVE-2021-27216